Introduction: I’m making this guide for several reasons, not least because I’m sad and have nothing better to do, or maybe I’m procrastinating from doing real work, but I’d also like to get down on paper some thoughts on the science of our pew pew guns and clear up some misconceptions or at least get a discussion going to better our understanding.   This guide is going to be a combination of actual science (well, as close as I can get to actual science ) and some personal experi